Added rewind to to_file where appropriate

lib/paperclip/storage/filesystem.rb

@@ -30,7 +30,12 @@ module Paperclip
       # Returns representation of the data of the file assigned to the given
       # style, in the format most representative of the current storage.
       def to_file style_name = default_style
-        @queued_for_write[style_name] || (File.new(path(style_name), 'rb') if exists?(style_name))
+        if @queued_for_write[style_name]
+          @queued_for_write[style_name].rewind
+          @queued_for_write[style_name]
+        elsif exists?(style_name)
+          File.new(path(style_name), 'rb')
+        end
       end
 
       def flush_writes #:nodoc:

lib/paperclip/storage/fog.rb

@@ -110,6 +110,7 @@ module Paperclip
       # style, in the format most representative of the current storage.
       def to_file(style = default_style)
         if @queued_for_write[style]
+          @queued_for_write[style].rewind
           @queued_for_write[style]
         else
           body      = directory.files.get(path(style)).body

lib/paperclip/storage/s3.rb

@@ -257,7 +257,10 @@ module Paperclip
       # Returns representation of the data of the file assigned to the given
       # style, in the format most representative of the current storage.
       def to_file style = default_style
-        return @queued_for_write[style] if @queued_for_write[style]
+        if @queued_for_write[style]
+          @queued_for_write[style].rewind
+          return @queued_for_write[style]
+        end
         filename = path(style)
         extname  = File.extname(filename)
         basename = File.basename(filename, extname)

test/storage/filesystem_test.rb

@@ -31,6 +31,12 @@ class FileSystemTest < Test::Unit::TestCase
       @dummy.save!
     end
 
+    should "always be rewound when returning from #to_file" do
+      assert_equal 0, @dummy.avatar.to_file.pos
+      @dummy.avatar.to_file.seek(10)
+      assert_equal 0, @dummy.avatar.to_file.pos
+    end
+        
     context "with file that has space in file name" do
       setup do
         rebuild_model :styles => { :thumbnail => "25x25#" }

test/storage/fog_test.rb

@@ -110,6 +110,12 @@ class FogTest < Test::Unit::TestCase
         directory.destroy
       end
 
+      should "always be rewound when returning from #to_file" do
+        assert_equal 0, @dummy.avatar.to_file.pos
+        @dummy.avatar.to_file.seek(10)
+        assert_equal 0, @dummy.avatar.to_file.pos
+      end
+            
       should "pass the content type to the Fog::Storage::AWS::Files instance" do
         Fog::Storage::AWS::Files.any_instance.expects(:create).with do |hash|
           hash[:content_type]

test/storage/s3_test.rb

@@ -335,6 +335,12 @@ class S3Test < Test::Unit::TestCase
     should "return a relative URL for Rails to calculate assets host" do
       assert_match %r{^avatars/stringio\.txt}, @dummy.avatar.url
     end
+
+    should "always be rewound when returning from #to_file" do
+        assert_equal 0, @dummy.avatar.to_file.pos
+        @dummy.avatar.to_file.seek(10)
+        assert_equal 0, @dummy.avatar.to_file.pos
+      end
     end
 
   context "Generating a secure url with an expiration" do